Field of the Invention
This invention relates to apparatus for countering scale formation in a fluid flow system.
The problem of scale formation in fluid conduits associated with oil wells, water wells, heat exchange systems and steam boilers is well known. In particular, the problem is acute where the mineral content of the fluids flowing in a well system is high, as this results in substantial deposition and scale formation in fluid conduits, pumps and other equipment associated with the well system and this eventually causes operational problems.
A number of solutions to the problem have been proposed, for example, as described in U.S. Pat. Nos. 3,448,034, 3,486,999 and Irish Pat. Specification No. 39035. The elongated rod described in the latter Specification has been found to be most successful. However, one problem with this apparatus is that the elongated rod itself becomes covered with scale after a period of use and thus its effectiveness diminishes over a period of time and eventually stops. Indeed, in some hot water systems where such rods are used at present, it is necessary to use a recirculating pump to minimize scaling of the rod, by pumping the water at sufficient speed to scour the rod surface and prevent scaling.
The reason why the elongated rod becomes covered in scale is not fully understood. However, it has been found that the elongated rod is effective in countering scale formation in fluid conduits until it is itself covered in scale.